J/A+A/628/A81ivo://CDS.VizieR/J/A+A/628/A81doi:10.26093/cds/vizier.36280081CDSScholz R.-D.ChojnowskiS.D.Hubrig S.2021-01-08T16:43:07Z2019-08-09T08:06:08ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frap-starsvisible-astronomytrigonometric-parallaxproper-motionsinfrared-photometrybroad-band-photometryeffective-temperatureKnowing the distribution of strongly magnetic Ap stars in the Hertzsprung-Russell diagram (HRD) allows us to study the evolution of their magnetic fields across the main sequence (MS). With a newly extended Ap star sample from APOGEE and available Gaia DR2 data, we can now critically review the results of previous studies based on Hipparcos data. To investigate our targets in the Gaia DR2 HRD, we need to define astrometric and photometric quality criteria to remove unreliable data from the HRD. We used the Gaia DR2 renormalised unit weight error RUWE as our main quality criterion. We considered known (close) binaries in our sample compared to their (partly affected) astrometry and used the Gaia DR2 data to find common parallax and proper motion (CPPM) wide companions and open cluster members. We studied G, BP and RP variability amplitudes and their significance as a function of magnitude. In colour-magnitude diagrams (CMDs) with absolute G magnitude (determined from inverted parallax) versus BP-RP colour and HRDs, where BP-RP is replaced by effective temperature, we studied the appearance of outliers with respect to their astrometric quality, binarity, and variability. We present a catalogue of 83 previously known and 154 new strongly magnetic Ap stars with Gaia DR2 data, including astrometric quality parameters, binary flags, information on cluster membership, variability amplitudes, and data from Hipparcos. Our astrometrically cleaned subsamples include 47 and 46 old and new Ap stars with parallaxes >2mas. Most of the known 26 binaries among all 237 stars and 14 out of 15 CMD/HRD outliers were excluded by astrometric criteria. The remaining 11 known binaries and a few highly variable objects mainly appear in the bright and red CMD/HRD parts. A CMD based on Hipparcos photometry and Gaia DR2 parallaxes shows a much more narrow distribution in the absolute V magnitudes of 75 common Ap stars over the full B-V colour range than the corresponding CMD based on Hipparcos parallaxes.2019A&A...628A..81Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/628/A81CatalogResearchIsServedByTAP VizieR generic servicerelated-toI/311 : Hipparcos, the New Reduction (van Leeuwen, 2007)I/345 : Gaia DR2 (Gaia Collaboration, 2018)J/A+A/601/A14 : Radial velocities of magnetic Ap stars (Mathys, 2017)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/628/A81https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/628/A81http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/628/A81https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/628/A81https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/628/A81http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/628/A81GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tap1.9867573869263685e-19 6.298446873438916e-19OpticalInfrareddefaultJ/A+A/628/A81/catalogGaia DR2-based Catalogue of magnetic Ap starsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintName(SIMBAD) name of Ap star, typically HD ... or 2MASS ... (1)meta.id;meta.maincharGaiaDR2Unique Gaia source designation (3)meta.idcharPlx? Gaia DR2 parallax (3)maspos.parallaxdoublenullablee_Plx? error of Gaia DR2 parallax (3)masstat.error;pos.parallaxfloatnullableRPlx? Gaia DR2 parallax divided by its error (3)stat.fit.omcdoublenullablepmRA? Gaia DR2 proper motion component in right ascension direction pmRA*cos(DE) (3)mas/yrpos.pm;pos.eq.radoublenullablee_pmRA? error of pmRA (3)mas/yrstat.error;pos.pm;pos.eq.rafloatnullablepmDE? Gaia DR2 proper motion component in declination direction (3)mas/yrpos.pm;pos.eq.decdoublenullablee_pmDE? error of pmDE (3)mas/yrstat.error;pos.pm;pos.eq.decfloatnullableNpGaia DR2 Nper = visibility\_periods\_used (3)stat.fit.omcintGmagGaia DR2 G magnitude (3)magphot.mag;em.optfloatBPmagGaia DR2 BP magnitude (3)magphot.mag;em.opt.BfloatBP-RPGaia DR2 BP-RP colour (3)magphot.color;em.opt.B;em.opt.RfloatuGaia DR2 astrometric unit weight error (3) (4) (11)stat.errordoubleRUWERenormalised unit weight error (newly calibrated u) (3) (5) (11) (4)stat.errordoublevaGVariability amplitude in Gaia DR2 G band (3) (11) (6)src.var.amplitude;em.opt.VfloatvaBVariability amplitude in Gaia DR2 BP band (3) (11)src.var.amplitude;em.opt.BfloatvaRVariability amplitude in Gaia DR2 RP band (3) (11)src.var.amplitude;em.opt.RfloatvaGsSignificance of vaG (number of standard deviations sigma above the typical level of non-variable stars) (3) (11)stat.fit.goodnessfloatvaBsSignificance of vaB (number of standard deviations sigma above the typical level of non-variable stars) (3) (11)stat.fit.goodnessfloatvaRsSignificance of vaR (number of standard deviations sigma above the typical level of non-variable stars) (3) (11)stat.fit.goodnessfloatTeffStellar effective temperature (3) (8)Kphys.temperature.effectivefloatb_TeffUncertainty (lower) on Teff estimate (3) (8)Kstat.error;phys.temperature.effectivefloatB_TeffUncertainty (upper) on Teff estimate (3) (8)Kstat.error;phys.temperature.effectivefloatLum? Estimated luminosity (3) (8)solLumphys.luminositydoublenullableGMAG? Absolute G magnitude computed as M_G_=G+5log(Plx/100) (3) (11)magphys.magAbsfloatnullablewfWide binary (common parallax and proper motion = CPPM) flag (number of CPPM companions) (3) (11)meta.codeintbfClose (with respect to Gaia measurements) binary flag (0 = not known as binary) (1)meta.codeintcfCluster membership flag (number of clusters of which the star is a member) (3) (11) (9)meta.code.errorintafAstrometric quality flag (number of criteria by which star was excluded, 0=best, 4=worst) (11) (3) (5)meta.code.qualintvfVariability flag (number of photometric bands, where the star lies >3sigma above the typical variability amplitude) (3) (11)meta.numberintHip? Hipparcos identifier (10)meta.idintnullableNNote in first version of Hipparcos catalogue, here: P = note on photometry (10)meta.idcharSn? Solution type new reduction, 5 = 5-parameter, 7 = 7-parameter solution, >9 = double star with peculiarities (10)meta.codeintnullableSo? Solution type old reduction, 0 = 5-parameter, 1 = 7- or 9-parameter, 3 = double/multiple stars, 4 = orbital binary (10)meta.codeintnullableNc? Number of components according to Hipparcos (10)meta.numberintnullableHPlx? Hipparcos parallax (new reduction) (10)maspos.parallaxfloatnullablee_HPlx? Error of Hipparcos parallax (new reduction) (10)masstat.errorfloatnullableNtr? Number of Hipparcos field transits used (10)meta.numberintnullableF2? Hipparcos goodness of fit (10)stat.fit.goodnessfloatnullableF1? Percentage of rejected Hipparcos data (10)stat.value;arith.ratiointnullableHPmag? Hipparcos magnitude (in the optical V band of the Hipparcos photometric system) (10)magphot.mag;em.opt.VfloatnullableB-V? Hipparcos B-V colour index (in the non-conventional system) (10)magphot.color;em.opt.B;em.opt.VfloatnullableV-I? Hipparcos V-I colour index (no standard system specified) (10)magphot.color;em.opt.V;em.opt.IfloatnullableSimbadSimbad column added by the CDSmeta.ref.urlchar